320 GENETICS [Bot. Absts. 



crossing-over, and independent inheritance of tunicate and yellow endosperm. Review 

 published results of other investigators and suggest three independent groups of linked 

 factors in maize. — R. A. Emerson. 



2145. Kajanus, Birger. Genetische Papaver-Notizen. [Genetical notes on Papaver.J 

 Bot. Notiser 1919: 99-102. 1919. — Under the term "Rhoeas-group" the author includes with 

 Papaver somniferum a number of commercial forms and the similar species P. u?nbrosu?n, 

 P. Hookeri, and P. laevigatum. The species P. pavonium and P. glaucum, being distinct, 

 are not included in this group. Members of the Rhoeas-group show considerable variation 

 in a number of characters: flower and leaf color, 'color of stem hairs, and color of latex. Many 

 of the types included in this group were almost or completely sterile when self-fertilized. 

 One plant from the group produced self ed seed, the plants from which resembled their parent 

 but they produced so few seeds that no conclusions were drawn regarding fertilization ratio. — 

 Four types of artificial crosses are recorded : 1. Those between plants within the Rhoeas-group. 

 2. P.rhoeas 9 X P. glaucum d\ 3. P. somniferum 9 X P. rhoeas cT. 4. P. somniferum 9 

 X glaucum d". Only crosses of the first two kinds produced positive results. Plants em- 

 ployed showed the following characters: white vs. yellow latex, light red vs. scarlet petals, 

 white eye-spot (Herzflerken) vs. black eyespot. The Fi plants showed segregation in latex 

 color (24 yellow, 32 white) and in eye-spot color (black 24, white 31). A system of dominant 

 and recessive genes is given in explanation of the alternative behavior of these characters. 

 None of these Fi plants produced fertile seed when self-fertilized. The cross rhoeas X glau- 

 cum produced 11 Fi plants which showed typical F! hybrid vigor. They, however, showed 

 some characters of both parents. Ten bagged flowers gave no selfed seed. Open-pollinated 

 seed produced plants resembling rhoeas. — J . L. Collins. 



2146. Kajanus, B. Uber eine konstant gelbbunte Pisum-Rasse. [On a constantly 

 yellow-variegated variety of Pisum.] Bot. Notiser 1918: 83-84. 1918. — Author found in an 

 Fs family of Pisum arvense punctatum X P. arvense maculatum besides normal green plants 

 also several yellow-variegated ones. The numerical relation of the two kinds of plants was 

 probably 3:1. An exact count was not undertaken however. Three yellow-variegated 

 plants gave (1) 55 yellow-variegated : 2 green; (2) 6:2; (3) 32:0. The occurrence of green 

 plants is probably due to hybridization with normal individuals. One specimen of (3) pro- 

 duced only yellow-variegated plants and their offspring had the same coloration. The 

 yellow-variegated variety is therefore constant. — K . V. Ossian Dahlgren. 



2147. Kajanus, B. Genetische Studien iiber die Bliiten von Papaver somniferum L. 

 [Genetical studies on the flowers of Papaver somniferum L. Arkiv Bot. K. Svensk. Veten- 

 skapsakad. 15 18 : 1-87. 3 pi. 1919 —Author has worked with about 20,000 plants. Double- 

 ness depends on absence of two homomeric genes. For the splitting of the sepals it seems that 

 at least three genes were operating. In the presence of these factors, entire petals can be 

 obtained through influence of an inhibiting factor. There are specific genes for color and 

 others which regulate the distribution of color. The color genes are divided into two groups, 

 one for violet, one for red. In each group there is one fundamental gene that produces the 

 weakest tint and a series of intensifying genes. Presence of the gene characteristic of the 

 violet groups, alone, makes the petals violet above as well as below. The presence of the 

 gene of the red group makes them red above and white below. If both genes are combined, 

 the colors become red on the upper and violet on the under side, whereas in the absence of 

 both genes the petals are white. The genes of distribution play a great role in the habit of 

 the flowers and affect also the shade of color. — One gene is associated with green-striping, 

 another with whito-striping of the petals. Also in relation to other anomalies special genes 

 are traced. — A'. V. Ossian Dahlgren. 



2148. Kajanus, B., and S. O. Berg. Pisum-Kreuzungen. [Pisum-crosses.] Arkiv 

 Bot. K. Svensk. Vetenskapsakad. 15 ia - 1-18. 1919. — A new inhibiting gene O is found, 

 which suppresses dark blood-red or red brown color of the seed-coats. The effects of five 

 other genes earlier treated by Lock (Ann. Roy. Bot. Gard. Peradenya 4. 1908) have also been 

 studied, — K. V. Ossian Dahlgren. 



